"We are working through threshold questions and we are doing it with a seriousness of purpose that I think Minister Livni would agree with me has not been present in a while," Kerry said at the U.S. ambassador to Italy's residence before meeting with Livni in private.

"We all believe that we're working with a short time span," Kerry said. "We understand the imperative to try to have some sense of direction as rapidly as we can."

Kerry called an April 29 Arab League proposal to revive Palestinian-Israeli peace talks "an important step forward" and said he spoke earlier in the day with Qatari Prime Minister Sheik Hamad bin Khalifa al-Thani, who outlined the proposal on behalf of the League.

Al-Thani, who is also Qatar's foreign minister, suggested the revival of the Arab Peace Initiative, introduced in 2002 and re-endorsed in 2007, but for the first time eased the League's demand that Israel return to its pre-1967 borders.

Instead, the minister accepted the possibility of tweaking those borders with a comparable and mutually agreed "minor swap of the land."

He said peace between the Palestinians and Israelis was "a strategic choice for the Arab states."

"They want to keep the progress moving," Kerry said Wednesday, adding so did he.

Livni, Israel's justice minister and a former foreign minister, praised Kerry's "enthusiasm and efforts" and said "they can change the reality," CNN reported.

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